In recent years, electronic devices including mobile phones, tablet personal computers (PCs), notebooks, or digital cameras have achieved high-performance and high-function, and thus various components have been implemented therein.
In addition, as the demand for high-lightweight and flexible electronic devices is increased, flexible components are actively developed.
Components incorporated in such electronic devices generate heat and electromagnetic waves when performing high-performance and multi-function. When the electromagnetic waves flow into components or flow out to the outside, a variety of electromagnetic disturbances are generated due to electromagnetic waves from malfunction of other electronic devices to negative effects on the human body.
Therefore, an electromagnetic shielding sheet is essentially used for an electronic device to prevent the electromagnetic waves from affecting the components.
Electromagnetic shielding technology can be divided into a method of shielding external devices by shielding the vicinity of an electromagnetic wave generating source and a method of protecting an electronic device inside a shielding material and protecting the electronic device from an external electromagnetic wave generating source.
At present, various technologies for enhancing electromagnetic shielding are continuously being developed, and it is necessary to develop a technology of an electromagnetic shielding sheet to be adhered or bonded to an electromagnetic wave generating source and to be connected to the ground.
Korean Patent Application Publication No. 2013-0136386 (Patent Document 1) discloses an electromagnetic shielding sheet including: a substrate which is produced into a nanoweb form by spinning a polymer material into a fiber strand by a spinning method; a conductive metal layer formed on one surface of the substrate and shielding electromagnetic waves; and an adhesive layer formed on the other surface of the substrate.
The adhesive layer of the electromagnetic shielding sheet of Patent Document 1 is formed by accumulating a plurality of fiber strands obtained by spinning an adhesive material. The adhesive layer has only an adhesive function for adhering the electromagnetic shielding sheet to an object. The electromagnetic shielding function cannot be performed due to electrical energization when the electromagnetic shielding sheet is adhered to an object.